Electrically-powered portable devices often include portable power sources, such as batteries, that must be recharged periodically. Many such devices also provide communications to a host device or other associated machinery, so as to exchange data relating to device operation, maintenance history, and the like. Recharging a portable device and exchanging data through a host device, which provides a power source, often involves receiving electrical power and communicating data over a single connection. Such connections may comprise, for example, a Universal Serial Bus (USB) connector coupling the portable device to a host computer or a USB hub. The portable device often must be constructed for operation so it is isolated from the source that provides electrical power for operation and for charging, and often must be isolated as well from the source of data exchange and communications. Such portable devices may include laboratory devices, portable test equipment, and portable user devices.
One example of a portable device such as described above is a device that involves the delivery of fluids. There are many applications in academic, industrial, and medical fields, as well as others, that involve devices capable of accurately and controllably delivering fluids, including liquids and gases, that have a beneficial effect when administered in known and controlled quantities. This is particularly true in the medical field, where treatments for many patients include the administration of a known amount of a substance at predetermined intervals. For example, the treatment of diabetes involves just such a regimented dosage of medicaments such as insulin. In addition, diabetes is one of a few medical indications wherein the patient routinely administers the medicament (such as insulin) to themselves by a subcutaneous modality, such as, e.g., via a hypodermic syringe injection or an ambulatory infusion device, or pump. This is an example wherein providing a patient with the safe, reliable, and comfortable administration of required doses of medication may be particularly important in order to facilitate patient compliance and accurate treatment of the condition. In view of the human involvement, government regulations and industry standards often impose requirements for control of electromagnetic emissions, power leakage, and the like.
Ambulatory insulin infusion pumps have been developed for the administration of medicaments such as insulin for those diagnosed with both type I and type II diabetes. These pumps offer an alternative to multiple daily injections of insulin by an insulin syringe or an insulin pen. They also allow for continuous insulin therapy. In addition, some ambulatory infusion devices can include data collection and storage mechanisms, which allow a diabetic patient/user and/or a caregiver (e.g., doctor, health care worker, family member, and so forth) to easily monitor and adjust insulin intake. The infusion device may be powered by a rechargeable battery that requires periodic recharging.
For safety, the user of a medical infusion device must be isolated from electrical hazards when handling the portable medical device during recharging. A “user” refers to a person who is operating the medical infusion device, and may comprise a patient, diabetic person, caregiver, and the like. Additionally, the user must be isolated from electrical hazards during everyday use. Such use can result in exposure to water and other liquids, e.g., sweat, which may come into contact with the device. When a conventional device becomes wet, the device can malfunction or shut down completely, or might produce an electrical shock to the user of the device. Accordingly, it is also desirable to protect the device in the case that it is exposed to water and liquids, so that the device is still capable of delivering insulin to the patient and maintaining data necessary for operation, while also preventing any bodily harm to the user and/or to the patient. As used herein, the term “user” will be understood to include a person who is a patient, and may include other persons such as caregivers, clinicians, certified diabetes instructors (CDEs), medical professionals, and the like, depending on the context in which “user” is mentioned.
There is a need for a portable device that safely facilitates user interaction, data collection, and recharging while providing electrical and data isolation. In this way, it is not necessary for the portable device to be removed from a patient while connecting the device to a power source or data communications host.